Every student will help prepare a Colby student energy audit of electric= al appliances used by the student body.=C2=A0 Start by claiming an applianc= e by adding your name to the table below.=C2=A0 You may fill in the rest of= your row at a later date.
Name 
Appliance 
Energy Consumption (J/year) 
Number on Campus 
Total Energy 

example 
microwave 
3.73 * 10^4 kJ/year 
1077.1 
4.01 * 10^7 kJ 
Sarah 
Cell chargers 
1.45 *10^7 J/year 
1764 
2.56 *10^7kJ 
Andy 
Laptop chargers 
4.60 E8 J/year 
1867 
8.59 E8 kJ 
Reuben 
Televisions 
99600kj/femaleyr; 24300kj/maleyr 
960 female; 790 male 
2.88 E8 kJ/yr 
Erin 
Hair Straighteners 
1.96 * 10^7 J/year 
966.7 
3.45 *10^7 kJ 
Rachael 
Lamps 
9.58 E7 J/yr 
1717 
1.65 E8 kJ 
Amy 
Refrigerators 
2.7 * 10^8 J/year 
600 
1.62 * 10^9 kJ 
Devon 
Speakers 
6.93 * 10^7 J/year 
1235 
8.56 * 10^7 kJ 
Mike 
Electric Razors 
1.79 * 10^3 J/year 
706 
1.26 * 10^5 kJ 
Kimberly 
clocks 
1.36 x 10^8 J/yr 
752 
2.4 x 10^8 kJ/yr 
Greg 
Coffee Maker 
1.281 x 10^5 kJ/year 
176.4 
2.260 x 10^7 kJ/yr 
Josie 
Microwave 
5.3 * 10^5 kJ/year 
875 
4.6 * 10^8 kJ 
Trevor 
Gaming Console 
=C2=A0 
=C2=A0 
=C2=A0 
Once you have selected the appliance, survey 10 or more rooms to get a s= tatistical sampling of the appliance frequency on campus.=C2=A0 Determine t= he energy consumed by the appliance over the course of the academic year an= d compute the total energy consumed by all students using the appliance.=C2= =A0 Put your data in the table above and provide the details on your applia= nce and your calculations below.=C2=A0 This assignment is only submitted on= this page.
Post answers to assignment 1 below:=C2=A0 (list name, appliance,=
and then details)
Steve Jobs, Apple laptop computer
=C2=A0=C2=A0=C2=A0 Details on the calculations for computer energy consu= mption ....
________________________________________________________________________= _______________________=C2=A0
Example, Blow Drier
=C2=A0 
Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Jilbere 
125 
10 
1250 
2 
Physique 
125 
15 
1875 
3 
Revlon 
125 
15 
1875 
4 
Conair 
125 
15 
1875 
5 
Perfection Classic 
125 
15 
1875 
6 
Vidal Sassoon 
125 
15 
1875 
7 
Conair 
125 
15 
1875 
8 
Conair 
125 
15 
1875 
9 
Conair 
125 
15 
1875 
10 
Conair 
125 
15 
1875 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
1812.5 
Average Energy Consuption a year assuming 10 minutes daily use.
1812.5 J/sec * 60 sec/min * 10 min/day * 365 day/year =3D 3.97E8 J
Assuming every female (54.8%) on campus and no males use a blow dryer (s= ome guys have hair driers)
3.97E8 J * 1867 * 54.8% =3D 4.06E11 J =3D 4.06E8 kJ
=C2=A0Electric Razors
Sample # 
Brand 
Use (min/week) 
Voltage (J/c) 
Current (c/sec) 
Power (J/sec) 

1 
Braun 
10 
12 
0.400 
4.8 
2 
Braun 
12 
12 
0.400 
4.8 
3 
No Razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
4 
No Razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
5 
No Razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
6 
Phillips Norelco 
7 
15 
0.420 
6.3 
7 
Phillips Norelco 
12 
15 
0.420 
6.3 
8 
No razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
9 
No razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
10 
No razor 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
Average 
40% of student body 
10.25 
=C2=A0 
=C2=A0 
5.6 
=C2=A0Average Energy Consumption:
5.6 J/sec * 60 sec/min * 10.25 min/week * 52 weeks/year =3D 1.79 * 10^3 = J/year
Assuming only males use electric shavers
1.79 * 10^3 J/razor/year * 1764 students * 0.40 razors/student * 1J/1000= kJ =3D 1.26 * 10^5 kJ/year
Devon McIntyre, iPod/Computer Speakers
Sample # 
Brand 
Voltage (V) 
Current (A) 
Power (W) 

1  Altec Lansing, 
100  240 
0.8 
80 
2  Logitech 
120 
0.525 
63 
3  Bose 
120 
0.16 
19.2 
4  Bose 
120 
0.16 
19.2 
5  JBL 
120 
0.183 
22 
6  JBL 
120 
0.183 
22 
7  JBL 
120 
0.183 
22 
8  Klipsch 
100  240 
max 1.5 
150 
9  iSymphony 
120 
0.9 
108 
10  JBL 
120 
0.183 
22 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
52.74 
Average energy consumption in a year assuming speakers are used 1 hour p= er day:
52.74 J/sec=C2=A0*=C2=A0 60 sec/1 min=C2=A0 *=C2=A060 min/1 day=C2=A0 *= =C2=A0 365 days/1 year=C2=A0 =3D=C2=A06.93 E7 J/year
Colby students total =E2=80=93 1838
% Colby students on campus =E2=80=93 96%
Total Colby students on campus =E2=80=93 1764
Assume 70% of students have speakers =E2=80=93 1764 =C2=A0*=C2=A0.70=C2= =A0 =3D=C2=A0 1235 students with speakers on campus
1235*=C2=A0* *=C2=A0 6.93 E7 J =C2=A0=3D =C2=A08.56 E10 J =C2=A0=3D=C2= =A0 8.56 E7 kJ/year
________________________________________________________________________= _______________________=C2=A0
Rachael Mack: Lamps
=C2=A0 
Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Walmart 
120 
0.5 
60 
2 
=C2=A0 
120 
0.33 
40 
3 
Your Zone 
120 
0.33 
(40*5 bulbs) 200W 
4 
=C2=A0 
120 
0.33 
40 
5 
Jansjo 
120 
0.09 
10.8 
6 
Jansjo 
100 
0.09 
0.09 
7 
Walmart 
120 
0.12 
14 
8 
=C2=A0 
120 
0.5 
60 
9 
=C2=A0 
120 
0.33 
40 
10 
Walmart 
120 
0.12 
14 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
48.78 
Assuming there is on average one lamp per person, and each person uses i= t daily for about 1.5 hours. (Approximately 93% of the total student body l= ives on campus =E2=80=93 1717 students.)
48.78 J/s * 60 s/min * 90 min/day * 365 day/yr =3D 9.61 E7 J/yr
9.61 E7 J/yr * 1717 students =3D 1.65 E8 kJ/yr
________________________________________________________________________=
_______________________=C2=A0
*Reuben Biel, Television*
Room No 
Brand 
Volt (V) 
Current (A) 
Wattage (W) 
Time (hrs_used/day) 
Occupants 
Gender 
kJ Used per Room per Day 
kJ Used per Individual per Day 
1 
Sylvania 
120 
0.44 
53 
0.57 
3 
M 
109.0285714 
36.34285714 
2 
Emerson 
120 
0.5 
60 
1 
2 
F 
216 
108 
3 
 
0 
0 
0 
0 
2 
M 
0 
0 
4 
Orion 
120 
0.92 
110 
1 
2 
F 
396 
198 
5 
Olevin 
120 
1 
100 
1.5 
3 
M 
540 
180 
6 
 
0 
0 
0 
0 
2 
F 
0 
0 
7 
 
0 
0 
0 
0 
3 
M 
0 
0 
8 
Emerson 
120 
0.46 
55 
1 
2 
F 
198 
99 
9 
Magnavox 
120 
2 
240 
0.57 
1 
M 
493.7142857 
493.7142857 
10 
Magnavox 
120 
0.33 
40 
5 
1 
M 
720 
720 
11 
RCA 
120 
0.46 
55 
1.5 
1 
F 
297 
297 
12 
LG 
120 
1.25 
150 
6 
1 
M 
3240 
3240 
13 
Insignia 
120 
0.58 
70 
0.5 
0.5 
F 
126 
 
13A 
LG 
120 
1.25 
150 
2 
0.5 
F 
1080 
 
13 Total 
=C2=A0 
0 
0 
0 
0 
1 
F 
0 
1206 
14 
 
0 
0 
0 
0 
1 
F 
0 
0 
Assuming that Televisions only draw energy while being used (false assum=
ption so is an underestimate of actual usage):
Average Usage per Female per Day (including those without TVs): 273 kJ/day<=
br />
Average Usage per Male per Day (including those without TVs): 667 kJ/day
If there are approx. 960 females (54.8%) and 790 males on campus (Total 175=
0 students), then:
Total Female Usage per Year =3D 273 kJ/femaleday*365 days/yr*960 females =
=3D 9.55E7kJ/yr
Total Male Usage per Year =3D 667 kJ/maleday*365 days/yr*790 males =3D 1.9=
2E8kJ/yr
Total Energy Usage per Year =3D 9.55E7kJ/yr + 1.92E8kJ/yr =3D 2.88E=
8kJ/yr
Kimberly Bittler, Electric alarm/radio clocks
 Room  Brand  Voltage (V)  Current (A) 
1 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
2 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
3 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
4 <= /td>  Timex <= /p> 
120 
0.05 
6 <= /td>  
5 <= /td>  Memorex= 
15 = 
1 <= /td>  15 = 

6 <= /td>  Sony 
120 
0.04 
5 <= /td>  
6 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
6 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
7 <= /td>  Sony 
120 
0.04 
5 <= /td>  
8 <= /td>  RCA 
22 = 
1 <= /td>  22 = 

8 <= /td>  iPod 
15 = 
1.5 
22.5 

9 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
9 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
9 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
10 = 
0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
11 = 
0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
12 = 
Sony 
120 
0.04 
5 <= /td>  
13 = 
0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  
14 = 
Sony 
120 
0.04 
5 <= /td>  
15 = 
Memorex= 
120 
0.04 
5 <= /td>  
16 = 
0 <= /td>  0 <= /td>  0 <= /td>  0 <= /td>  =C2=A0 
Number of students with alarm clocks:
9/21 students in the survey =3D 43 % x ~1750 students on campus =3D 752 = students
Average power use of alarm clocks: 10.0 W
Total Average power use (including nonowners): 4.3 W
Yearly Average Power Use per student:
4.3 J/sec x 60 sec/min x 60 min/hr x 24 hr/day x 365 day/yr =3D 1.36 x 1= 0^8 J/yr
Campus Power use:
1.36 x 10^8 J/yr x 1750 students =3D 2.40 x 10^11 J/yr x 1 kJ/1000 J
Josie Thiele, Microwave Oven
=C2=A0 
Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Cuisinart 
120 
8 
1000 
2 
=C2=A0 
120 
8 
1000 
3 
GE 
120 
9 
1100 
4 
=C2=A0 
120 
9 
1100 
5 
LG 
120 
13 
1500 
6 
=C2=A0 
120 
13 
1500 
7 
=C2=A0 
120 
13 
1500 
8 
Sharp 
120 
9 
1100 
9 
=C2=A0 
120 
9 
1100 
10 
Frigidaire 
150 
6 
900 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
1180 
Assuming that there is one microwave per room (and each room has 2 peopl= e in it), and each room uses it for 20 minutes a day.=C2=A0
Yearly Average Power Use per microwave
1180J/s*60s/min*20min/day*365day/yr*1kJ/1000J=3D5.2*10^5kJ/yr
Annual Campus Power Use
Assuming there is one per room, ~875 rooms
5.2*10^5kJ*875rooms=3D4.6*10^8kJ/yr
*Erin SchnettlerHair Straightners
Sample 
Brand 
Voltage (V) 
Power (W) 
1 
Emperor 
110V 
200W 
2 
Solia 
110V 
58W 
3 
Sedu 
110V 
72W 
4 
Solia 
110V 
58W 
5 
CHI 
110V 
35W 
6 
Sedu 
110V 
72W 
7 
Conair 
120V 
36W 
8 
Solia 
110V 
58W 
9 
Hot Tools 
110V 
170W 
10 
Solano 
110V 
135W 
Avg. 
89.4W 

Average Energy Consumption per year assuming 10 minutes of daily use 89.4J/sec*(60sec/min)(10min/day)(365days/year)=3D19578600 = J/year
Avg. Energy Consumption per year assuming that use is limited to all f=
emales on campus:
19578600 J * 1,764 students * .548 =3D3.454*10^10 J (1 kJ/1000 J) =3D 3.45*=
10^7 kJ/year
________________________________________________________________________= _______________________=C2=A0
Greg Klein: Coffee Makers
=C2=A0 
Brand 
Voltage (V) 
Current (A) 
Power (W) 
1 
Mr. Coffee 
120 
7.5 
900 
2 
=C2=A0 
120 
7.5 
900 
3 
Black and Decker 
120 
10 
1200 
4 
Cuisinart 
120 
13.833 
1660 
5 
=C2=A0 
120 
13.833 
1660 
6 
Cuisinart 
120 
9.166 
1100 
7 
=C2=A0 
120 
9.166 
1100 
8 
Hamilton Beach 
120 
7.5 
900 
9 
Hamilton Beach 
120 
12 
1140 
10 
=C2=A0 
120 
12 
1140 
Average 
1812.5 

Assuming about one in ten students has a coffee maker:<= /p>
0.1 x 1764 students =3D 176.4 students
Average yearly power consumption, assuming 5 minutes daily use:<= /strong>
1170 J / sec x 60 sec / min * 5 min x 365 =3D 1.281 x 10^8 J / year
Total power consumption for the campus:
1.281 x 10^8 (J / year x students) x 176.4 students =3D 2.260 x 10^10 J = / year
2.260 x 10^7 kJ / year
Andy Oakes, Laptop Chargers
> Sample  Brand  Voltage  Current  Power 
1 
Macbook 
16.5V 
3.65A 
60W 
2 
Macbook Pro 
16.5V 
3.65A 
60W 
3 
Dell Latitude 
19.5V 
3.34A 
65W 
4 
Dell Inspiron 
19.5V 
3.34A 
65W 
5 
Macbook Pro 
16.5V 
4.6A 
85W 
6 
HP Compaq 
19V 
4.74A 
90W 
7 
Macbook Pro 
16.5V 
3.65A 
60W 
8 
Macbook 
16.5V 
3.65A 
60W 
9 
Dell Inspiron 
19.5V 
3.34A 
65W 
10 
Gateway NV 
19V 
4.74A 
90W 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
70W 
Average Energy Consuption a year assuming 300 minutes daily use.
70 J/sec * 60 sec/min * 300 min/day * 365 day/year =3D 4.60E8 J/year
Assuming everyone on campus has a laptop
4.60E8 J * 1867 =3D 8.59E11 J =3D 8.59E8 kJ
Sarah Dallas Cell Phone Chargers
sample 
brand 
voltage (V) 
current (A) 
Power (W) 

1  LG  5  1  5 
2  BlackBerry 
5  0.7 
3.5 
3  BlackBerry 
5  0.7 
3.5 
4  Samsung 
5  0.7 
3.5 
5  LG  5.1 
0.7 
3.57 
6  LG  5.1 
0.7 
3.57 
7  Motorola 
5  0.55 
2.75 
8  LG  4.8 
0.9 
4.32 
9  LG  5.1 
0.7 
3.57 
10  BlackBerry 
5  0.7 
3.5 
Average 
=C2=A0 
=C2=A0 
=C2=A0 
3.678 
1764 chargers on campus, because every student has a cell phone
Assume they are used by everyone for 3 hours a day every day of the year=
3.678 J/sec * 60 sec/min * 60 min/hr * 3 hr/day * 365 days/yr =3D
Power*#of chargers >> 1.45E7 * 1764 =3D 2.56E10 J >> 2.56E7 kJ
Trevor Poole  Game Consoles
Sample # 
Brand 
Use (min/week) 
Voltage (V) 
Current (A) 
Power (W) 

1 
Xbox 360 
120 
12 
12.1 
150 
2 
None 
0 
0 
0 
0 
3 
None 
0 
0 
0 
0 
4 
Xbox 360 
60 
12 
14.2 
175 
5 
None 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
6 
Wii 
90 
12 
3.7 
33 
7 
None 
0 
0 
0 
0 
8 
Xbox 360 
90 
12 
14.2 
175 
9 
Wii 
90 
12 
3.70 
33 
10 
None 
=C2=A0 
=C2=A0 
=C2=A0 
=C2=A0 
40% of rooms total have game consoles, however all surveyed were male. 1= 764 total students * (.4 (males on campus) * .5 (males with game consoles))= =3D.2 total, or 353 game consoles on campus
Used for an average of 90 minutes per day
113.2J/s * 60seconds/minute * 60 mins/hour * 1.5 hours/ day * 365 days/y= ear =3D 223,117.2 kJ per year per console.
223,117.2 kJ * 353 consoles =3D 78,760,371.6 kJ
Amy Holmen, mini fridges
Sample 
Brand 
Votage (V) 
Current (A) 
Power (W) 

1  GE  120 
0.75 
90 
2  MagicChef 
115 
1.2 
138 
3  MagicChef 
115 
1.3 
149 
4  Sanyo 
120 
1.0 
120 
5  Haier 
110 
1.1 
121 
6  Danby 
120 
0.85 
102 
7  none 
     
8  GE  120 
0.75 
90 
9  none 
     
10  MagicChef 
115 
1.2 
138 
=C2=A0 
=C2=A0 
=C2=A0 
AVERAGE 
118.5 
Yearly Average power use per fridge
Let us assume that the fridge is plugged in and running all day for 9 mo= nths of the year (our school year)
118.5 J/sec * 60 sec/1 min * 60 min/1hr * 24 hr/day * 270 day/year=3D 2.= 7 *10^6 kJ per year per fridge
Annual Campus Power Use
Assume that 80% of rooms have a fridge, so 750 rooms * 0.80=3D 600 fridg= es on campus
2.7*10^6 kJ/year/fridge * 600 fridges=3D 1.62*10^9 kJ/year
Some Links to get things started
http://blogs.middlebury.edu/biomass/
http://www.colgate.edu/DesktopDefault= 1.aspx?tabid=3D4354
http://www.fs.fed.us/woodybiomass/state.shtml
http://www.aashe.org/wiki/= climateplanningguide/carbonoffsets.php
http://alethonews.wordpress.com/2010/0= 1/12/upinsmoke/
Questions to consider:
1) It is generally assumed that Maine is harvesting wood at a rate equal=
to the annual growth rate.=C2=A0=C2=A0 Is this true?=C2=A0 What are Maine=
=E2=80=99s requirements for sustainable growth?
2) If question one is true, how does a biomass plant meet the additional= ly principle for carbon neutrality?=C2=A0 Do we have additional biomass cap= acity in Maine?
3) Using Middlebury=E2=80=99s wood consumption as a guide, how many acre= s of forest are required to meet the fuel requirements of the proposed biom= ass plant at Colby?=C2=A0=C2=A0How many acres of forest will need to be har= vested to meet Colby=E2=80=99s fuels supply in a sustainable fashion?
A) Divide the class into groups of four and decide which group will addr= ess which question.
B) Starting with the resources provided at the beginning of this questio= n, generate an annotated bibliography of sources to help answer your questi= on.
C) Generate two figures diagramming the material flows used to help answ= er your question.
D) For class on Friday, 2/26.=C2=A0=C2=A0 Be prepared to present your tw= o figures and your strategy for answering your group question.
Works Cited
Gibbs, Jeff. "Green Nightmare: Burning Biomass is Not Renewable Ene= rgy." The Huffington Post. 17 Dec. 2009. Web. 23 Feb. 2010. &= lt;http://www.hu= ffingtonpost.com/jeffgibbs/greennightmareburningb_b_395553.html>= .=C2=A0
The Gibb=E2=80=99s article gives an opposing view, explaining why biomas= s generated energy is not a renewable energy source.
MaineForest Service. MaineForest Service Assessment of Sustainable B= iomass Availability. Rep. Maine State Government, 17 July 2008. Web. 2= 4 Feb. 2010. <http://www.maine.g= ov/doc/mfs/pubs/pdf/biomass_memo_071708.pdf>.
The Maine Forest Service Report provided information regarding the curre= nt biomass of Maine's forests, and the sustainable yield for the forests.
MiddleburyCollege. "Biomass at Middlebury." The Middlebury= Blog Network. Web. 24 Feb. 2010. <http://blog= s.middlebury.edu/biomass/about/>.
The Middlebury site was used to obtain general as well as specific infor= mation regarding the use of biomass technology at MiddleburyCollege. This i= nformation was used to determine what would be necessary for Colby to use b= iomass technology.
National Alliance of Forest Owners. "Carbon Neutrality of Energy fr= om Forest Biomass." Carbon Neutrality of Energy from Forest B= iomass. NAFO (National Alliance of Forest Owners), 2009. Web. 23 Feb. 2010.= <http://nafoalliance= .org/carbonneutralityofenergyfromforestbiomass/>.
The National Alliance of Forest Owners site provides background informat= ion in regards to the carbon neutrality of producing energy from forest bio= mass.
Sarah, Kim, Reuben, and Trevor
Book Problems  Chapter 9: 4, 6, 9, 12, 13
Additional Problems
1.=C2=A0 Freon, CFC12, is building up in the atmosphere at a rate of 1.=
4 %/year.=C2=A0If the current concentration of CFC12 is 519 pptv (parts pe=
r trillion by volume), what is the net molar flux of CFC12 to the atmosphe=
re in one year?=C2=A0
2. Calculate the maximum wavelength of radiation that could have suffici=
ent energy to effect the dissociation of nitric oxide (NO).=C2=A0In what re=
gions of the atmosphere would such radiation be available? (The bond energy=
of NO is 90.2 kJ/mol)
3. The Chapman mechanism of stratospheric ozone production was successfu= l at predicting the shape of the stratospheric ozone concentration profile,= but overestimated the ozone concentration.=C2=A0 We now understand that si= mple ozone models involving only O_{2}, O and O_{3}species = are incomplete.=C2=A0 What are the major processes controlling the stratosp= heric ozone concentration profile (shape and concentration) and how have at= mospheric emissions in the last 50 years modified the profile.=C2=A0 (HW Key )
Book Problems 11: 2, 7, 9, 14, 13: 4, = 7, 11,17
Additional Problem:=C2=A0 During a recent talk at the Maine Water Qualit= y Conference, Professor Steve Kahl from UMO showed convincing evidence of d= ecreased acid deposition to Maine based on decreasing sulfate concentration= s in Maine lakes.=C2=A0 During the same 10 year period the nitrate concentr= ations have also decreased, but much more slowly.=C2=A0 Explain these findi= ngs in terms of the chemistry of =E2=80=9Cacid rain=E2=80=9D including curr= ent regulations, atmospheric chemistry, and emission sources.
Lake Problem Set=C2=A0I.=C2=A0
Consider a lake of infinite horizontal dimension, a depth of 20 meters, =
and a thermoclineat 10 meters.=C2=A0The epilimnetic temperature is 25 ^{=
o}C.=C2=A0=C2=A0=C2=A0 The hypolimnetic temperature is 6^{o}C.=
=C2=A0=C2=A0 Both layers are well mixed vertically.=C2=A0The alkalinity of =
the lake is 0.10 mM.
1) Calculate the equilibrium concentration of oxygen at depths of 5 and =
15 meters in units of ppm and moles/liter.
2) If the average wind speed on the lake is 10 meters/second, what rate =
of net biological oxygen demand (moles/liter sec) is required to decrease t=
he oxygen concentration to 90% of saturation at 5 meters?
3) Based on the biological oxygen demand, how long will it take the hypo= limnion to go anoxic (<1 ppm O2)?
Key:=C2=A0 Lake prob= lem 2010 O2 solubility.xls
Lake Problem Set=C2=A0II.=C2=A0
Consider a lake of infinite horizontal dimension, a depth of 20 meters, = and a thermocline at 10 meters.=C2=A0The epilimnetic temperature is 25 oC.=C2=A0=C2=A0=C2=A0 The hypolimnetic temperature is 6^{o} = C.=C2=A0=C2=A0 Both layers are well mixed vertically.=C2=A0The alkalinity o= f the lake is 0.10 mM.
1) Calculate the pH of the epilimnion assuming it is in equilibrium with= CO_{2} in the atmosphere.
2) Assuming that the phosphate concentration of the lake was 20 ppb (as = P) at the time of the spring turnover, calculate the oxygen concentration i= n the lake at 5 meters=C2=A0 and 15 meters after all the P in the epilimnio= n is consumed by photosynthesis, settles, and is respired in the hypolimnio= n.
3) What is the pH of the hypolimnion after the event described in step 2= occurs?
4)=C2=A0 By how much will the nitrate in the hypolimnion increase after = the event described in step 2 occurs?
=_Part_2818_1581753545.1542625910432